1. Field of the Invention
The present invention relates to an image forming apparatus and an image forming method with which a raised print image is formed by transferring an image resulting from foaming toner and an image resulting from non-foaming toner onto a recording medium in correspondence to print image information and utilizing thermal expansion of the foaming toner.
2. Background Art
Conventionally, technology using embossing, technology using dot impact, and technology using foam paper and heat transfer film have been known as technology that forms a raised image on a recording medium such as recording paper.
However, in the conventional technology, there are problems in terms of cost, and problems in durability and preservability. The technology is therefore only used for limited purposes.
Thus, the present applicant has proposed image forming apparatus that form a raised image using foaming toner in JP-A-2000-131875 (Title of the invention: Image Forming Toner, Method of Preparing the Image Forming Toner, and Image Forming Apparatus and Method of Forming a Raised image Using the Image Forming Toner) and in JP-A-2001-194846 (Title of the invention: Image Forming Apparatus).
The technologies disclosed in these publications make it possible to easily and inexpensively form a raised image that has excellent durability and preservability with a common electrophotographic printer or copying machine by using foaming toner.
However, these technologies cannot form a full-color raised image simply by being able to form a monochromatic raised image.
In a case where a full-color raised image is to be formed using foaming toner, the full-color raised image cannot be formed by simply superposing plural foaming toners including respectively different coloring materials and transferring the foaming toners to a recording medium. The reason for this is because it is difficult to achieve full color resulting from color layering, because the foaming toners do not have light transmittance characteristics in a foamed state.
Thus, the present applicant has proposed a structure in which a full-color raised image that has excellent durability and preservability is inexpensively formed by transferring foaming toner onto a recording medium and transferring thereon non-foaming ordinary toners of respective colors.
However, in this structure, multiple transfer, in which plural toner images are transferred, becomes necessary when the toner images are transferred to an intermediate transfer body or to the recording medium.
In particular, because color transmittance is low, it is necessary for foaming toner forming a raised print to be directly formed on a recording medium such as paper in a final print.
Accordingly, when the foaming toner is transferred to an intermediate transfer body, the foaming toner must be transferred at the very last.
When three-dimensionally printing fine lines and small regions, problems arise in that reproduced fine lines and images of small regions are partially omitted, which results in an unclear image, because transfer and fixing to the recording paper is carried out in a state in which the foaming toner is similarly disposed on fine color toner images on the intermediate transfer body.
Thus, it is an object of the present invention to provide an image forming apparatus and an image forming method with which fine lines and small regions are reproduced as a raised image with excellent quality.
In order to achieve the object the invention provides an image forming apparatus that forms a raised print image by successively transferring foaming toner and non-foaming toner onto a recording medium in correspondence to print image information and heat-fixing onto the recording medium the foaming toner and the non-foaming toner that have been transferred onto the recording medium. The image forming apparatus includes an image processing section that image-processes the print image information so that transfer of an image resulting from the foaming toner is selectively prohibited in correspondence to a line width or size of an image to be transferred by the non-foaming toner onto the foaming toner.
The invention further provides an image forming apparatus including an image processing section that image-processes the print image information so that a line width or size of an image to be transferred by the non-foaming toner onto the foaming toner is corrected in correspondence to a line width or size of an image to be transferred by the non-foaming toner onto the foaming toner.
The invention further provides an image forming apparatus including an image processing section that image-processes the print image information. The image processing section separates the print image information into a first region that mainly includes text information and a second region that mainly includes image information. The image processing section selectively transfers the foaming toner to the entity of an image in the first region or the entity of an image in the second region.
The invention further provides an image forming method, including: transferring foaming toner onto a recording medium; transferring non-foaming toner onto the recoding medium, while selectively prohibiting transfer of an image resulting from the foaming toner in correspondence to a line width or size of an image to be transferred by the non-foaming toner onto the foaming toner; and heat-fixing onto the recording medium the foaming toner and the non-foaming toner to thereby form a raised print.
The invention further provides an image forming method, including: transferring foaming toner onto a recording medium; transferring non-foaming toner onto the recoding medium, while correcting a line width or size of an image to be transferred by the non-foaming toner onto the foaming toner in correspondence to a line width or size of an image to be transferred by the non-foaming toner onto the foaming toner; and heat-fixing onto the recording medium the foaming toner and the non-foaming toner to thereby form a raised print.
The invention further provides an image forming method, including: separating an image to be transferred to a recording medium into a first region and a second region, the first region mainly including text information, the second region mainly including image information; transferring foaming toner onto the recording medium, while selectively carrying out transfer of the foaming toner with respect to the entity of an image of the first region or the entity of an image of the second region; transferring non-foaming toner onto the recoding medium; and heat-fixing onto the recording medium the foaming toner and the non-foaming toner to thereby form a raised print.
The invention further provides a recording medium, including a medium body; and a raised print image formed on the medium body. The raised print image includes a first layer and a second layer. The second layer is superimposed on the first layer. The first layer is made from forming toner. The second layer is made from non-forming toner and is divided into a plurality of regions each forms small images smaller in size than the entity of the raised print image. Line widths or sizes of the small images are smaller than a predetermined line width or size. The plurality of regions are formed on at least a portion of the first layer formed successively on the medium body.